class TaskQueue():
    def put(self, a):

        self.__list.append(a)

    def pop(self):

        if self.is_empty():
            return None;
        return self.__list.pop(0)

    def delete(self, index):

        if self.is_empty():
            return False;
        if (index >= 0) and (index < self.count()):
            self.__list.pop(index)
        return True

    def __init__(self):
        self.__list = []

    def count(self):
        return len(self.__list)

    def is_empty(self):
        '''鍒ゆ柇鍒楄〃鏄惁涓虹┖'''
        return self.__list == []

    def getItem(self, index):
        if index < 0:
            return None
        if index > len(self.__list) - 1:
            return None
        return self.__list[index]

    def setItem(self, index, a):
        if index < 0:
            return None
        if index > len(self.__list) - 1:
            return None
        self.__list[index] = a
        return True

    def getList(self):
        return self.__list